Carton with improved strength sidewall panels

ABSTRACT

A carton formed from a blank of foldable corrugated sheet material having two pairs of upstanding generally parallel sidewall panels and a pair of first flaps hingedly foldably connected to the upper and lower edges of each sidewall panel along a fold line, the flaps configured to form a panel for covering the bottom and top of the carton when the carton is assembled and wherein cuts for support tabs are made into the corrugated material along the fold lines such that when the cover-forming flaps are folded 90 degrees to form the bottom cover of the carton, the support tabs remain oriented in the planes of the sidewall panels. The carton may further comprise cuts for corner support tabs made into the corrugated material at each of the locations where the fold lines overlap adjacent sidewall panels, such that when the cover-forming flaps are folded 90 degrees to form the bottom or top cover of the carton, the corner support tabs remain oriented in the planes of the sidewall panels.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims benefit of priority under 35 U.S.C. Section 119(e) to U.S. Provisional application Ser. No. 61/381610, filed Sep. 10, 2010, entitled “Carton With Angled Corner Panels,” which is hereby incorporated herein by reference.

Field of the Invention

The present invention relates to cartons with sidewall panels having improved resistance to distortion from vertical loads.

BACKGROUND OF THE INVENTION

Many cartons containing products are stored or transported under conditions in which vertical pressures are imposed upon the cartons from applied loads such as in multiple layer stacked configurations. Accordingly, to provide protection for the products, cartons must have substantial vertical strength to prevent buckling and deformation.

SUMMARY OF PARTICULAR EMBODIMENTS OF THE INVENTION

The present invention, in one embodiment, provides a carton formed from a single sheet of corrugated material, having three or more sidewall panels and one or more foldable flaps at the upper and lower edges of the sidewall panels. These flaps may form the bottom and top panels of the carton. These cover-forming flaps may have tab-shaped cuts in the corrugated material along the fold line to form support tabs along the upper and lower edges of the sidewall panels, when the cover-forming flaps are folded 90 degrees to form the cover of the carton. The top surfaces of these support tabs are formed by cuts in the corrugated material along a plane orthogonal to the vertically-oriented flutes of the corrugated material, and parallel to the bottom and top panels of the carton. These support tabs form portions of the upper and lower edges of the sidewall panels, which are cut, as opposed to folded, such that the upper and lower surfaces of the vertically-oriented corrugated material of the support tabs maintains the open flute configuration. This open flute configuration of the upper tab surface provides a substantially flat and wider load-bearing surface with greater resistance to buckling and distortion than folded edges, which necessarily crimp the flutes in the corrugated material. This support tab configuration at the top and bottom edges of the wall panels also provides wall panels which are strong and prevent crushing of the container during storage or handling operations. The support tabs are preferably dimensioned to extend slightly above the bottom and top panels of the carton, which are formed by the folding of the flaps at the upper and lower edges of the sidewall panels. Thus, the carton will rest on top of a supporting surface by contact with the lower surfaces of the vertically-oriented corrugated material of the support tabs on the lower edges of the sidewall panels. The support tabs provide support along the outer perimeter of the bottom panel of the carton, much like the legs of a table, resulting in improved stability, particularly when compared to conventional cartons with folded bottom panels, which may tend to bulge or bow towards the center. By the use of support tabs along the folds between the sidewalls and the bottom and top panels of the carton, this configuration provides a more stable top and bottom surface for resting on a flat supporting surface and for stacking of cartons in multiple layers.

Additionally, because the portions of the upper and lower edges of the sidewall panels where the support tabs are formed are cut rather than folded, the edges formed along the folded corners between the sidewalls and the bottom and top panels of the carton are more nearly perpendicular, thus reducing or eliminating the bulging that may result in the sidewall and top and bottom panels of the carton. By allowing a more nearly perpendicular fold between the sidewalls and the bottom and top panels of the carton, this configuration provides a more stable top and bottom surface for resting on a flat supporting surface and for stacking of cartons in multiple layers.

BRIEF DESCRIPTION OF THE DRAWINGS

The above mentioned and other features and objects of this invention and the manner of attaining them will become more apparent and the invention itself will be better understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings.

FIG. 1 is a perspective view of the assembled carton according to the present invention illustrating the support tabs cuts along the fold line between the flaps and the upper and lower edges of the sidewall panels and the resulting fluted bearing surfaces at the corners and around the perimeters of the bottom and top panels of the carton.

FIG. 2 is a plan view of the interior face of an unjoined, unfolded blank for the carton of FIG. 1.

FIG. 3 is a plan view of a joined, unfolded blank of FIG. 2.

FIG. 4 is a perspective view of a portion of the assembled carton of FIG. 1 illustrating the orthogonal cuts along the fold line between the flaps and the upper and lower edges of the sidewall panels and the resulting fluted bearing surfaces at the corners and around the perimeters of the bottom and top panels of the carton.

FIG. 5 is a perspective view of the assembled carton according to another embodiment of the present invention illustrating the support tabs cuts along the fold line between the flaps and the upper and lower edges of the sidewall panels and the resulting fluted bearing surfaces at the corners of the bottom and top panels of the carton.

FIG. 6 is a plan view of the interior face of an unjoined, unfolded blank for the carton of FIG. 5.

FIG. 7 is a plan view of a joined, unfolded blank of FIG. 6.

FIG. 8 is a perspective view of a portion of the assembled carton of FIG. 5 illustrating the orthogonal cuts along the fold line between the flaps and the upper and lower edges of the sidewall panels and the resulting fluted bearing surfaces at the corners of the bottom and top panels of the carton.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

The drawings illustrate, among other things, various examples of embodiments of the invention, and certain examples of characteristics thereof. Other embodiments may differ. Different embodiments of the invention include various combinations of elements or acts shown in the drawings, described herein, known in the art, or a combination thereof, for instance.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

Referring to FIGS. 1 and 2, according to one embodiment of the present invention, there is shown a carton 10 which is formed of a sheet blank 12 of corrugated material, such as cardboard or the like. As shown in FIG. 2, the unitary blank 12 includes sidewall panels 14, 16, 18 and 20. In this preferred embodiment, sidewall panels 14 and 18 constitute one pair of parallel sidewall panels, and sidewall panels 16 and 20 constitute another pair of parallel sidewall panels.

As shown in FIG. 2, cuts for the support tabs 22 are made into the corrugated material along the horizontal fold lines 50. These cuts form the support tabs 22 along the upper and lower edges of the sidewall panels when the cover-forming flaps 30, 32, 38 and 40 are folded 90 degrees along the horizontal fold lines 50 to form the top and bottom covers of the carton 46 and 48 (not visible), as shown in FIG. 1.

Also as shown in FIG. 2, cuts for corner support tabs 24 may also be made into the corrugated material along the horizontal fold lines 50 where they extends across adjacent sidewall panels such as, for example, across adjacent sidewall panels 14 and 16, or across adjacent sidewall panels 18 and 20. These cuts for corner support tabs 24 will form the 90 degree corner support tabs 24 along the upper and lower edges of the sidewall panels when the adjacent sidewall panels 14, 16, 18 and 20 of the unfolded blank 12 are folded 90 degrees from one another to form the two pairs of parallel side panels of a four-sided carton, and the cover-forming flaps 30, 32, 38 and 40 are folded 90 degrees along the horizontal fold lines 50 to form the top and bottom covers of the carton 46 and 48, as shown in FIG. 1.

It should be noted that FIG. 2 illustrates the interior face of the blank 12, and the dotted lines 26 are vertical fold lines between adjacent sidewall panels 14, 16, 18 and 20 along which blank 12 is folded inwardly toward the viewer in order to form the wall panels thereof as further described hereinafter. Similarly, the dotted lines 50 are the horizontal fold lines along which the cover-forming flaps 30, 32, 38 and 40 are folded 90 degrees inwardly toward the viewer from the sidewall panels 14, 16, 18 and 20 in order to form the top and bottom covers of the carton 46 and 48, as shown in FIG. 1.

An overlap portion 28 adjoins sidewall 20 whereby, when blank 12 is joined, overlap portion 28 may be secured to sidewall 14 such as by means of an adhesive.

FIG. 3 illustrates a blank 12 in a joined configuration, such that overlap portion 28 has been secured to sidewall 14, such as by means of an adhesive.

As shown in FIGS. 1 and 2, a top flap 30 adjoins sidewall 14 at the top and bottom flap 38 adjoins sidewall 14 from the bottom. Similarly, top flap 32 adjoins sidewall 18 at the top, and bottom flap 40 adjoins sidewall 18 at the bottom.

Also as shown in FIGS. 1 and 2, a top flap 34 also adjoins sidewall 16 at the top and bottom flap 42 adjoins sidewall 16 from the bottom. Similarly, top flap 36 adjoins sidewall 20 at the top, and bottom flap 44 adjoins sidewall 20 at the bottom.

Also as shown in FIGS. 1, and 4, in a preferred embodiment of the present invention, the top flaps 30, 32, 34 and 36 of the respective upstanding sidewall panels 14, 18, 16 and 20 are folded and sealed to form the top panel 46 of the carton 10. Similarly, bottom flaps 38, 40, 42 and 44 of the respective upstanding sidewall panels 14, 18, 16 and 20 are folded and sealed to form the bottom panel 48 of the carton 10.

As shown in FIGS. 1 and 4, when the cover-forming flaps are folded 90 degrees to form the cover of the carton, the cuts along the horizontal fold lines 50 form the support tabs 22 along the upper and lower edges of the sidewall panels and the 90 degree corner support tabs 24 at the upper and lower corners of the sidewall panels.

As shown in FIGS. 1 and 4 the upper surfaces of the support tabs 22 and the 90 degree corner support tabs 24 are cut such that the vertically-oriented corrugated material of the tabs maintains the open flute configuration, thus providing a substantially flat and wider load-bearing surface with greater resistance to buckling and distortion than folded edges, which necessarily crimp the flutes in the corrugated material. This support tab and corner support tab configuration at the top and bottom edges of the wall panels also provides wall panels which are strong and prevent crushing of the container during storage or handling operations.

Also as shown in FIGS. 1 and 4, the support tabs 22 and corner support tabs 24 are preferably dimensioned to extend slightly above the bottom and top panels of the carton formed by the folding of the flaps at the upper and lower edges of the sidewall panels. Thus, the carton will rest on top of a supporting surface by contact with the lower surfaces of the vertically-oriented corrugated material of the support tabs 22 and corner support tabs 24 on the lower edges and corners of the sidewall panels.

Alternatively, the support tabs 22 and corner support tabs 24 may be dimensioned to extend at or near the upper and lower surfaces of the top panel 46 and bottom panel 48 of the carton 10 formed by the folding of the flaps at the upper and lower edges of the sidewall panels. By selectively dimensioning the support tabs 22 and corner support tabs 24, the bearing load may be distributed as desired between the support tabs 22 and corner support tabs 24, and the upper and lower surfaces of the top panel 46 and bottom panel 48 of the carton 10.

Also as shown in FIGS. 1 and 4, the corner support tabs 24 form a 90 degree self-reinforcing structure having substantial strength, rigidity, and resistance to crushing or deformation.

FIGS. 5-8 depict another embodiment of the present invention illustrating the corner support tabs 24 cuts along the horizontal fold lines 50 between the flaps and the upper and lower edges of the sidewall panels and the resulting fluted bearing surfaces at the corners of the bottom and top panels of the carton.

As shown in FIGS. 5, and 8, in this preferred embodiment of the present invention, the top flaps 30, 32, 34 and 36 of the respective upstanding sidewall panels 14, 18, 16 and 20 are folded and sealed to form the top panel 46 of the carton 10. Similarly, bottom flaps 38, 40, 42 and 44 of the respective upstanding sidewall panels 14, 18, 16 and 20 are folded and sealed to form the bottom panel 48 (not shown) of the carton 10.

Also as shown in FIGS. 5 and 8, when the cover-forming flaps are folded 90 degrees to form the cover of the carton, the cuts along the horizontal fold lines 50 form the 90 degree corner support tabs 24 at the upper and lower corners of the sidewall panels.

As shown in FIG. 6, cuts for corner support tabs 24 are made into the corrugated material along the horizontal fold lines 50 where they extends across adjacent sidewall panels such as, for example, across adjacent sidewall panels 14 and 16, or across adjacent sidewall panels 18 and 20. These cuts for corner support tabs 24 will form the 90 degree corner support tabs 24 along the upper and lower edges of the sidewall panels when the adjacent sidewall panels 14, 16, 18 and 20 of the unfolded blank 12 are folded 90 degrees from one another to form the two pairs of parallel side panels of a four-sided carton, and the cover-forming flaps 30, 32, 38 and 40 are folded 90 degrees along the horizontal fold lines 50 to form the top and bottom covers of the carton 46 and 48, as shown in FIG. 5.

As shown in FIGS. 5 and 8, the corner support tabs 24 are preferably dimensioned to extend slightly above the bottom and top panels of the carton formed by the folding of the flaps at the upper and lower edges of the sidewall panels. Thus, the carton will rest on top of a supporting surface by contact with the lower surfaces of the vertically-oriented corrugated material of the corner support tabs 24 on the lower edges and corners of the sidewall panels.

Alternatively, the corner support tabs 24 may be dimensioned to extend at or near the upper and lower surfaces of the top panel 46 and bottom panel 48 of the carton 10 formed by the folding of the flaps at the upper and lower edges of the sidewall panels. By selectively dimensioning the corner support tabs 24, the bearing load may be distributed as desired between the corner support tabs 24 and the upper and lower surfaces of the top panel 46 and bottom panel 48 of the carton 10.

Also as shown in FIGS. 5 and 8, the corner support tabs 24 form a 90 degree self-reinforcing structure having substantial strength, rigidity, and resistance to crushing or deformation.

Although the foregoing described embodiments relate to four-sided cartons, the present invention also encompasses embodiments of cartons with three or more sidewall panels, including, for example, a triangular or hexagonal cartons with sidewall support tabs and/or corner support tabs.

In essence, in one embodiment the present invention comprises a carton formed from a blank of foldable corrugated sheet material having two pairs of upstanding, generally parallel sidewall panels, pairs of first flaps hingedly foldably connected to each of the first pair of said parallel sidewall panels along fold lines, the flaps configured to form panels for covering the top and bottom of the carton when the carton is assembled, and wherein cuts for support tabs are made into the corrugated material along the fold lines such that when the cover-forming flaps are folded 90 degrees to form the bottom cover of the carton, the support tabs remain oriented in the plane of the respective sidewall panel.

In essence, in another embodiment the present invention comprises a carton formed from a blank of foldable corrugated sheet material having two pairs of upstanding, generally parallel sidewall panels, a pair of first flaps hingedly foldably connected to each pair of said parallel sidewall panels along a fold line, the flaps configured to form a panel for covering the top or bottom of the carton when the carton is assembled, and wherein cuts for corner support tabs are made into the corrugated material at each of the four locations where the fold lines extend across adjacent sidewall panels such that when the cover-forming flaps are folded 90 degrees to form the top or bottom cover of the carton, the corner support tabs remain oriented in the planes of the sidewall panels.

In essence, in another embodiment the present invention comprises a carton formed from a blank of foldable corrugated sheet material having at least three upstanding sidewall panels, flaps hingedly foldably connected to each of at least two of said sidewall panels along the fold lines, the flaps configured to form panels for covering the top and bottom of the carton when the carton is assembled, and wherein cuts for support tabs are made into the corrugated material along the fold lines and cuts for corner support tabs are made into the corrugated material at each of at least three locations where the fold lines extend across adjacent sidewall panels such that when the cover-forming flaps are folded 90 degrees to form the top and bottom cover of the carton, the support tabs and corner support tabs remain oriented in the plane of the respective sidewall panel.

While this invention has been described as having preferred designs, it will be understood that it is capable of further modification. This application is therefore intended to cover any variations, uses or adaptations of the invention following the general principles thereof and including such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and fall within the limits of the appended claims. 

What is claimed is:
 1. A carton formed from a blank of foldable corrugated sheet material comprising: two pairs of upstanding, generally parallel sidewall panels; a pair of first flaps hingedly foldably connected to each of the first pair of said parallel sidewall panels along a fold line, the flaps configured to form a panel for covering the bottom of the carton when the carton is assembled, and wherein cuts for support tabs are made into the corrugated material along the fold lines such that when the cover-forming flaps are folded 90 degrees to form the bottom cover of the carton, the support tabs remain oriented in the plane of the respective sidewall panel.
 2. The carton according to claim 1 further comprising a pair of second flaps hingedly foldably connected to each of the first pair of said parallel sidewall panels along a fold line, the flaps configured to form a panel for covering the top of the carton when the carton is assembled, and wherein cuts for support tabs are made into the corrugated material along the fold lines such that when the cover-forming flaps are folded 90 degrees to form the top cover of the carton, the support tabs remain oriented in the plane of the respective sidewall panel.
 3. The carton according to claim 1 further comprising a pair of second flaps hingedly foldably connected to each of the second pair of said parallel sidewall panels along a fold line, the flaps configured to form a portion of a panel for covering the bottom of the carton when the carton is assembled, and wherein cuts for corner support tabs are made into the corrugated material at each of the four locations where the fold lines extend across adjacent sidewall panels such that when the cover-forming flaps are folded 90 degrees to form the bottom cover of the carton, the corner support tabs remain oriented in the planes of the sidewall panels.
 4. A carton formed from a blank of foldable corrugated sheet material comprising: two pairs of upstanding, generally parallel sidewall panels; a pair of first flaps hingedly foldably connected to each pair of said parallel sidewall panels along a fold line, the flaps configured to form a panel for covering the bottom of the carton when the carton is assembled, and wherein cuts for corner support tabs are made into the corrugated material at each of the four locations where the fold lines extend across adjacent sidewall panels such that when the cover-forming flaps are folded 90 degrees to form the bottom cover of the carton, the corner support tabs remain oriented in the planes of the sidewall panels.
 5. The carton according to claim 4 further comprising a pair of second flaps hingedly foldably connected to each pair of said parallel sidewall panels along a fold line, the flaps configured to form a panel for covering the top of the carton when the carton is assembled, and wherein cuts for corner support tabs are made into the corrugated material at each of the four locations where the fold lines extend across adjacent sidewall panels such that when the cover-forming flaps are folded 90 degrees to form the top cover of the carton, the corner support tabs remain oriented in the planes of the sidewall panels.
 6. A carton formed from a blank of foldable corrugated sheet material comprising: at least three upstanding sidewall panels; a flap hingedly foldably connected to each of at least two of said sidewall panels along a fold line, the flaps configured to form a panel for covering the bottom of the carton when the carton is assembled, and wherein cuts for support tabs are made into the corrugated material along the fold lines such that when the cover-forming flaps are folded 90 degrees to form the bottom cover of the carton, the support tabs remain oriented in the plane of the respective sidewall panel.
 7. The carton according to claim 6 further comprising a flap hingedly foldably connected to each of at least two of said sidewall panels along a fold line, the flaps configured to form a panel for covering the top of the carton when the carton is assembled, and wherein cuts for support tabs are made into the corrugated material along the fold lines such that when the cover-forming flaps are folded 90 degrees to form the top cover of the carton, the support tabs remain oriented in the plane of the respective sidewall panel.
 8. The carton according to claim 6 wherein the carton comprises three sidewall panels and wherein cuts for corner support tabs are made into the corrugated material at each of at least three locations where the fold lines extend across adjacent sidewall panels such that when the cover-forming flaps are folded 90 degrees to form the top cover of the carton, the corner support tabs remain oriented in the planes of the sidewall panels. 